Flight Controls/Stabilizers: Loose Fastener with the Engine Extension/Retraction Mechanism

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FAA Aircraft Certification Service SPECIAL AIRWORTHINESS INFORMATION BULLETIN SAIB: CE-09-22 SUBJ: Flight Controls/Stabilizers: Loose Fastener with the Engine Extension/Retraction Mechanism Date: March 30, 2009 This is information only. Recommendations aren’t mandatory.

Introduction

This Special Airworthiness Information Bulletin informs you, an owner or operator of a Schempp- Hirth model Janus C sailplane (S/N 87 through 252 inclusive) or a Janus CT (S/N 1 through 6 inclusive) powered sailplane, of an airworthiness concern.

Background

Schempp-Hirth Modification Bulletin No. 809-18 (for Janus CT) and Technical Note No. 295-25 (for Janus C), previously published in 1992 and 1994 respectively, optionally introduced an enlarged fin/rudder unit and/or a stiffer horizontal stabilizer. In 1999, the German airworthiness authority, Luftfahrt-Bundesamt, issued Airworthiness Directive (AD) number 1999-265 to address a flutter condition on these enlarged elevator/rudder units and require the installation of heavier elevator balance weights. However, the announcements issued by Schempp-Hirth did not incorporate the new balance weights as required by the LBA AD. As a result, some sailplanes or powered sailplanes modified after the LBA AD can have inconsistent maintenance data and have unintentionally reverted to the older and lighter elevator balance weights.

The European Aviation Safety Agency (EASA) has issued Airworthiness Directive No. 2009-0054, dated March 6, 2009. This AD requires an update to the maintenance data and a check of the hinge moments and balancing weights of the elevator and rudder surfaces. This AD only applies to serial numbers that have been modified with an enlarged fin/rudder unit and not equipped with a stiffer horizontal stabilizer. Sailplanes equipped with the original smaller fin/rudder unit are not affected.

The EASA AD corrects the inconsistency and the possibility for improper hinge moments and elevator/rudder balance weights identified above in the LBA AD.

Recommendations

These sailplanes are not type certificated in the United States and, therefore, the condition is not addressed by FAA AD action. However, these sailplanes could be operating in the United States with an experimental airworthiness certificate or other means. We recommend all owners and operators comply with actions outlined in EASA AD 2009-0054.

For Further Information Contact

Gregory Davison, Aerospace Engineer, FAA Small Airplane Directorate, Room 301, 901 Locust Street, Kansas City, Missouri 64106; telephone: (816) 329-4130; facsimile: (816) 329-4090; email: [email protected]

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Schempp-Hirth Flugzeugbau GmbH Krebenstrasse 25 D-73230 Kirchheim/Teck Germany Phone: +49 7021 7298 317 Fax: +49 7021 7298 199 Email: [email protected]